Amino Acids Proline Research Articles

How amino acids intercalate in CaFe layered double hydroxides: A combined RIXS and NEXAFS study.

Two-dimensional layered double hydroxides (LDHs) are ideal candidates for a large number of (bio)catalytic applications due to their flexible composition and easy to tailor properties. Functionality can be achieved by intercalation of amino acids (as the basic units of peptides and proteins). To gain insight on the functionality, we apply resonant inelastic soft x-ray scattering and near edge x-ray absorption fine structure spectroscopy to CaFe LDH in its pristine form as well as intercalated with the amino acids proline and cysteine to probe the electronic structure and its changes upon intercalation. We observe the activation of pristine LDH defect states by soft x-rays and their passivation by the intercalated molecules. The nitrogen at the amino amino is found to form C=NH+ bonds and thus generating positive charge at the amino group, moving it away from the positively charged LDH layers. The carboxyl group in cysteine is deprotonated and thus in zwitterionic state after intercalation. This negative charge is used to compensate the positive layer charge. For intercalated proline the spectral signature of a protonated carboxyl group is observed, however, we find orbital overlap to defects at the layer surfaces indicating strong interaction with the carboxyl groups.

Chiral recognition of amino acids through homochiral metallacycle [ZnCl2L]2.

Chiral recognition holds tremendous significance in both life science and chemistry. The ability to differentiate between enantiomers is crucial because one enantiomer typically holds greater biological relevance while its counterpart is often not only unnecessary but also potentially harmful. In this regard, homochiral metallacycle [ZnCl2L]2 is used in this study to understand and differentiate between the R and S enantiomers of amino acids (alanine, proline, serine, and valine). The electronic, geometric, and thermodynamic stabilities of the amino acid enantiomers inside the metallacycle are determined through various analyses. The greater interaction energy (Eint) is obtained for the ser@metallacycle complexes i.e., -33.03 and -30.75 kcal mol-1, respectively for the S and R enantiomers. The highest chiral discrimination energy of 3.11 kcal mol-1 is achieved for ala@metallacycle complexes. Regarding the electronic properties, the frontier molecular orbital (FMO) analysis indicates that the energy gap decreases after complexation, which is confirmed through density of states (DOS) analysis. Moreover, natural bond orbital (NBO) analysis determines the amount and direction of charge transfer i.e., from metallacycle towards amino acids. The maximum NBO charge transfer is observed for S-pro@metallacycle complex i.e., -0.291 |e|. Electron density difference (EDD) analysis further proves the direction of charge transfer. Noncovalent interaction index (NCI) and quantum theory of atoms in molecules (QTAIM) analyses demonstrate that the noncovalent interactions present between the host and guest are the weak van der Waals forces and hydrogen bonding. The results of NCI and QTAIM analyses for all the complexes are in alignment with those of the interaction energy (Eint) and chiral discrimination energy (Echir) analyses, i.e., significantly greater non-bonding interactions are observed for the complexes with greater Echir, i.e., for ala@metallacycle. Overall, our analyses demonstrate the excellent chiral discrimination ability of metallacycle towards chiral molecules, i.e., for enantiomers of amino acids through host-guest supramolecular chemistry.

Proline and ROS: A Unified Mechanism in Plant Development and Stress Response?

The proteinogenic amino acid proline plays crucial roles in both plant development and stress responses, far exceeding its role in protein synthesis. However, the molecular mechanisms and the relative importance of these additional functions of proline remain under study. It is well documented that both stress responses and developmental processes are associated with proline accumulation. Under stress conditions, proline is believed to confer stress tolerance, while under physiological conditions, it assists in developmental processes, particularly during the reproductive phase. Due to proline’s properties as a compatible osmolyte and potential reactive oxygen species (ROS) scavenger, most of its beneficial effects have historically been attributed to the physicochemical consequences of its accumulation in plants. However, emerging evidence points to proline metabolism as the primary driver of these beneficial effects. Recent reports have shown that proline metabolism, in addition to supporting reproductive development, can modulate root meristem size by controlling ROS accumulation and distribution in the root meristem. The dynamic interplay between proline and ROS highlights a sophisticated regulatory network essential for plant resilience and survival. This fine-tuning mechanism, enabled by the pro-oxidant and antioxidant properties of compartmentalized proline metabolism, can modulate redox balance and ROS homeostasis, potentially explaining many of the multiple roles attributed to proline. This review uniquely integrates recent findings on the dual role of proline in both ROS scavenging and signaling, provides an updated overview of the most recent research published to date, and proposes a unified mechanism that could account for many of the multiple roles assigned to proline in plant development and stress defense. By focusing on the interplay between proline and ROS, we aim to provide a comprehensive understanding of this proposed mechanism and highlight the potential applications in improving crop resilience to environmental stress. Additionally, we address current gaps in understanding and suggest future research directions to further elucidate the complex roles of proline in plant biology.

Proline-Selective Electrochemiluminescence Detecting a Single Amino Acid Variation Between A1 and A2 β-Casein Containing Milks.

The proline amino acid and prolyl residues of peptides/proteins confer unique biological and biochemical properties that motivates the development of proline-selective analysis. The study focuses on one specific class of problem, the detection of single amino acid variants involving proline, and reports a Pro-selective electrochemiluminescence (ECL) method. To develop this method, the A1-/A2- variants of milk's β-casein protein are investigated because it is a well-established example and abundant samples are readily available. Specifically, β-casein has 209 amino acids with 34 (or 35) proline residues: the A1-variant has a Pro-to-His substitution at position 67 (relative to the A2 variant). The study shows that proline's strong luminescence allows the generic discrimination of: Pro from other amino acids; an A2-oligopeptide from an A1-oligopeptide; the A2-β-casein variant from the A1-variant; and commercially-available A2 milks from A1-containing regular milks. The evidence indicates that luminescence depends on proline content and accessibility, as well as signal quenching. Compared to conventional immunoassays, the ECL method is simple, rapid, and inexpensive. Further, the ECL-method is Pro-selective (vs molecularly-selective like typical immunoassays) which should make it broadly useful for studying the role of proline in biology and especially useful for tracking the digestion of proline-rich proteins in the diet.

Assessing the drought-tolerance and growth-promoting potential of strawberry (Fragaria × ananassa Duch.) rhizobacteria for consortium bioformulation

Plant growth-promoting rhizobacteria (PGPR) are known to influence plant root cells to regulate and induce specific traits related to growth promotion and survival. In the present study, rhizobacteria from strawberry plants were screened for stress tolerance under osmotic stress in TSB-mediated PEG 6000 (-0.73 MPa) and tested their ability to produce proline, exopolysaccharide, and free amino acids, all of which induce and regulate stress tolerance. The rhizobacteria were also distinguished for the production of 1-aminocyclopropane-1-carboxylate deaminase (ACCd) for the mitigation of drought stress. Among the 111 rhizobacterial isolates, 41 isolates grow above threshold limit in osmotic stress tolerance, 33 of which exhibited stress tolerance. Further characterization screened 27 isolates as capable growth promoters. Among the experimentally screened rhizobacteria, the isolates SBU4 and SDK8 [Pseudomonas fluorescens (OP627557) (PGPR1) and Pseudomonas glycinae (OP627558) (PGPR2)] exhibited the most promising phyto-beneficial potential. Both the isolates grew exponentially well during the log phase, with increased growth in Log CFU ml-1 under experimentally produced osmotic stress. The drought stress tolerance test results of the SBU4 and SDK8 isolates revealed the presence of proline (1.93 μg mL-1, 2.05 μg mL-1), exopolysaccharide (2.19 mg mg-1 protein, 2.58 mg mg-1 protein), and free amino acid (11.47 μmol g-1, 13.32 μmol g-1) and positive growth in ACCd-enriched DF media, an ACCd assay (α-ketobutyrate (0.56 μmol/ml, 0.64 μmol/ml) and ammonia (0.37 μg mL-1, 0.53 μg mL-1)). The isolates SBU4 and SDK8 performed well in qualitative tests for P solubilization, N fixing ability, siderophore chelation, HCN, and ammonia production, as well as in assays involving P producers (94.57 μg mL-1 and 92.86 μg mL-1), siderophore units (52.14% SU and 63.12% SU), and IAA producers (74.63 μg mL-1 and 72.64 μg mL-1). These rhizobacterial isolates were optimized under various growth factors (pH, temperature, incubation) to achieve a relatively high log CFU ml-1. The isolates achieved maximum Log CFU mL-1 when cultured in either a specific range of pH or temperature or growth period (incubation) under standard test conditions. The growth of cultures on cross-streaked nutrient agar plates was tested for an efficient, effective consortium bioformulation that enhances growth and specific traits (drought stress mitigation) in strawberry plants.

Biobased ionic liquid solutions for an efficient post-combustion CO2 capture system

This study explores the use of ionic liquids (ILs) as a novel and efficient alternative to conventional monoethanolamine (MEA) for CO2 capture. While MEA scrubbing is well-known for carbon sequestration, it faces limitations such as high energy consumption, toxicity, and rapid degradation. In contrast, ILs offer advantages such as non-volatility, stability, and reduced corrosiveness. We focus on a biodegradable IL comprising choline ([Cho]) and proline ([Pro]) amino acids to create an eco-friendly solution. Dimethyl sulfoxide (DMSO) is introduced as a diluent to mitigate viscosity issues during CO2 uptake. Our research measures the thermo-physical properties, including density and viscosity of [Cho][Pro] in DMSO at different concentrations. The addition of DMSO resulted in a viscosity reduction of >97 % at a temperature of 303 K for the three virgin solutions compared to the pure IL. In addition, the CO2 capture performance was evaluated using a system of absorption and desorption reactors. The results show that the 25 % wt [Cho][Pro] solution excels, achieving over 90 % CO2 absorption, 0.66 molCO2/molIL in the first cycle, and demonstrating high reusability and regeneration efficiency over multiple cycles. Comparisons indicate that the IL solution outperforms traditional aqueous MEA solutions. Longer term testing confirms the solution's stability and minimal degradation, achieving a regeneration efficiency of >55 % over 30 cycles, suggesting the potential of [Cho][Pro] for sustainable long-term CO2 capture applications.

Mechanism of action of the toxic proline mimic azetidine 2-carboxylic acid in plants.

Plants have an amazing capacity to outcompete neighboring organisms for space and resources. Toxic metabolites are major players in these interactions, which can have a broad range of effectiveness by targeting conserved molecular mechanisms, such as protein biosynthesis. However, lack of knowledge about defensive metabolite pathways, their mechanisms of action, and resistance mechanisms limits our ability to manipulate these pathways for enhanced crop resilience. Nonproteogenic amino acids (NPAAs) are a structurally diverse class of metabolites with a variety of functions but are typically not incorporated during protein biosynthesis. Here, we investigate the mechanism of action of the NPAA azetidine-2-carboxylic acid (Aze), an analog of the amino acid proline (Pro). Using a combination of plate-based assays, metabolite feeding, metabolomics, and proteomics, we show that Aze inhibits the root growth of Arabidopsis and other plants. Aze-induced growth reduction was restored by supplementing L-, but not D-Pro, and nontargeted proteomics confirm that Aze is misincorporated for Pro during protein biosynthesis, specifically on cytosolically translated proteins. Gene expression analysis, free amino acid profiling, and proteomics show that the unfolded protein response is upregulated during Aze treatment implicating that Aze misincorporation results in accumulation of misfolded proteins triggering a global stress response. This study demonstrates the mechanism of action of Aze in plants and provides a foundation for understanding the biological functions of proteotoxic metabolites.

The effect of the drug "Epin-extra" on increasing the resistance of Fragaria х ananassa Duch. varieties to spring frosts

Relevance. A crucial condition for maintaining the vital potential of plants is their ability to with-stand adverse environmental conditions. The aim of the work was to study the effect of the drug "Epin-extra" on strengthening the resistance of Fragaria х ananassa Duch. plants for spring frosts.Methods. The objects: strawberry garden Queen and Harvest CGL. With the onset of active growth in the spring period non-root treatments of strawberry plants with were carried out with a solution of the Epin-extra growth regulator containing 24-epibrassinolide. During budding phase, the plants were exposed to negative temperatures in a controlled environment chamber (-3oC) "Espec" PSL-2KPH (Japan). The functioning of the antioxidant defense system and the activity of lipid peroxidation processes in membranes lipids (POL) based on the accumulation of malondialdehyde (MDA) were carried out in the leaves of strawberry varieties.Results. It was shown that the non-root treatment of strawberry varieties with the Epin-extra preparation contributed to a decrease in the processes of peroxidation of cell membranes. The content of malondialdehyde (MDA) was 10,2% lower by the Tsaritsa variety, and the variety the Urozhainaya CGL by 30,1% compared to the control. The amount of the amino acid proline in the Tsaritsa variety was 13,6 % higher compained to the control, and in the Urozhainaya CGL variety by 12,4%. Treatment with Epin-extra contributed to an increase in the amount of sugars in the leaf tissue of both varieties.

Effects of supplementation with freeze-dried Clostridium butyricum powder after replacement of fishmeal with cottonseed protein concentrate on growth performance, immune response, and intestinal microbiota of Litopenaeus vannamei

The present study was designed to investigate the effects of supplementation with freeze-dried Clostridium butyricum (CB) powder on the growth, immune function and intestinal health of Litopenaeus vannamei after replacing fishmeal in the diet with cottonseed protein concentrate (CPC). Six treatment groups were designed, namely the control group (CON, 25% fish meal) and five alternative groups (CPC replacing 40% fishmeal protein in the control group). Based on the alternative group, 0%, 0.065%, 0.26%, 1.04%, and 4.16% of freeze-dried CB bacterial powder (4.6 × 108 CFU/g) were added, recorded as CB 0, CB 0.065, CB 0.26, CB 1.04, and CB 4.16, respectively. Each treatment had 3 replicates of 40 shrimps (0.29 ± 0.01 g) each and breeding for 8 weeks. After the experiment, serum enzyme activities, muscle amino acids, and intestinal parameters (short-chain fatty acids, digestive enzymes, gene expression, and microbiota) were tested to explore the effects of freeze-dried CB powder in shrimp aquaculture. The results showed that the CB1.04 group had the highest final body weight, weight gain rate, and specific growth ratio (P > 0.05). Freeze-dried CB powder increased the activity of serum superoxide dismutase, glutathione peroxidase, complement 3, and complement 4. Muscle tyrosine, proline, and total essential amino acids were remarkably increased in the CB 1.04 group (P < 0.05). Propionic acid levels were elevated in the CB 1.04 and CB4.16 groups (P < 0.001). The relative expression of Dorsal, Relish, and Target of Rapamycin (TOR) genes was significantly increased in the CB 1.04 group (P < 0.01). Actinobacteria and Demequina abundance was significantly higher in the CB 1.04 group (P < 0.01). The results of the Vibrio parahaemolyticus challenge test showed the highest cumulative mortality rate (43.33%) in the CB0 group and the lowest cumulative mortality rate (20%) in the CB1.04 group. This study confirmed that freeze-dried CB powder alleviated the negative effects of CPC replacement of fish meal protein in Litopenaeus vannamei, and the optimum additive level was 2.11% (9.71 × 109 CFU/kg) as indicated by binary regression analysis of specific growth ratio.

Amino Acid Adsorption Onto Magnetic Nanoparticles Reveals Correlations With Physicochemical Parameters

AbstractWe analyze the adsorption of the proteinogenic amino acids (AAs) glutamine, glutamic acid, lysine, tyrosine, proline, and valine onto bare iron oxide nanoparticles (approx. 10 nm). Aiming to identify the governing principles of low molecular weight coronae, which remain underinvestigated, our study covers broad concentration ranges up to the solubility limit of the AAs. Isothermal experiments reveal that the highly soluble AAs valine, proline, and lysine form extensive multilayers on the nanoparticle surface, and infrared measurements indicate intermolecular interactions, particularly with valine and lysine, for higher AA contents. Conversely, the low solubility of tyrosine and glutamic acid restricts their adsorption capacity, despite their higher partitioning on the solid surface. Parameters derived from fitting a classic saturation model seem to align with well‐documented physicochemical properties such as the hydrophobicity and the complexity indices – a promising first step towards formulating design principles. Scaling these parameters by the AA solubility reveals a clear correlation with the adsorption behavior. In adsorption experiments with AA model mixtures, sequential incubation increases the adsorption capacity for valine and proline, whereas simultaneous incubation with these AAs reduces tyrosine's capacity. Future studies should seek to elucidate adsorption patterns to advance our understanding of corona growth and evolution mechanisms.

Functional role of the c-terminal domains of the msl2 protein of drosophila melanogaster

Dosage compensation complex, consisting of five proteins and two non-coding RNAs roX, specifically binds to the X chromosome in males, providing a higher level of gene expression, which is necessary to compensate for the monosomy of the sex chromosome in male Drosophila compared to two X chromosomes in females. The MSL2 protein contains an N-terminal RING domain, which acts as an E3 ligase in the ubiquitination of proteins and is the only subunit of the complex that is expressed only in males. The functional role of two C-terminal domains of the MSL2 protein, enriched with proline (P-domain) and basic amino acids (B-domain), was investigated. As a result, it was shown that the B-domain destabilizes the MSL2 protein, which is associated with the presence of two lysines whose ubiquitination is under the control of the RING domain of MSL2. The unstructured proline-rich domain stimulates transcription of the roX2 gene, which is necessary for the effective formation of the dosage compensation complex.

Determination of the Effects of Pear-Morchella Intercropping Mode on M. sextelata Quality, Yield, and Soil Microbial Community.

The intercropping of Morchella in pear orchards has important production value in improving the utilization rate and economic benefits of the orchard; however, there is little research on the intercropping model of pear-Morchella. In this study, metabolomics analysis found that compared with greenhouse cultivation, there were 104 and 142 metabolites significantly increased and decreased in the intercropping mode of M. sextelata, respectively. Among them, there was a significant accumulation of amino acids (phenylalanine, lysine, proline, citrulline, and ornithine), sugars (arabinitol and glucosamine), and organic acids (quinic acid, fumaric acid, and malic acid) related to the unique taste of Morchella in intercropping cultivation. In addition, research on the cultivation model using exogenous nutrient bags indicated that placing the density of six exogenous nutrient bags per square meter was most suitable for yield formation. Adding pear sawdust to the nutrient bags (PN) significantly increased the yield of morel per unit area. Moreover, soil microbial community analysis showed that fungal alpha diversity dramatically declined in PN-cultivated soil, which decreased the relative abundance of soil-borne fungal pathogens, including Fusarium and Aspergillus. Some beneficial soil bacteria abundance increased in the PN-used soil, such as Pedobacter, Pseudomonas, and Devosia. This study provides novel insights into the effects of intercropping on the internal quality of Morchella and enriches the theoretical knowledge on the consummation of the pear-Morchella model formation, further improving agricultural resource utilization efficiency and crop productivity.

Serum metabolomics signature of maternally inherited diabetes and deafness by gas chromatography-time of flight mass spectrometry.

The aim of this study was to identify a metabolic signature of MIDD as compared to healthy controls and other types of diabetes. We performed a comprehensive serum metabolomic analysis using gas chromatography-time of flight mass spectrometry (GC-TOFMS) in participants diagnosed with MIDD (n = 14), latent autoimmune diabetes in adults (LADA) (n = 14), type 2 diabetes mellitus (n = 14), and healthy controls (n = 14). Each group was matched for gender and age. There were significant metabolic differences among MIDD and other diabetic and control groups. Compared with control, MIDD patients had high levels of carbohydrates (glucose, galactose, mannose, sorbose, and maltose), fatty acids (2-Hydroxybutyric acid, eicosapentaenoic acid, and octadecanoic acid), and other metabolites (alanine, threonic acid, cholesterol, lactic acid, and gluconic acid), but low level of threonine. Compared with LADA, MIDD patients had high levels of threonic acid and some amino acids (alanine, tryptophan, histidine, proline, glutamine, and creatine) but low levels of serine. Compared with type 2 diabetes mellitus, MIDD patients had high levels of citrulline, creatine, 3-Amino-2-piperidone, but low levels of ornithine, fatty acids (arachidonic acid and octadecanoic acid), and intermediates of the tricarboxylic acid cycle (malic acid and succinic acid). Our study identified a specific metabolic profile related to glycolysis and the tricarboxylic acid cycle in MIDD that differs from healthy controls and other types of diabetes. This unique metabolic signature provides new perspectives for understanding the pathophysiology and underlying mechanisms of MIDD.

Features of influenza virus hemagglutinin genes and their recoding possibilities

The world has already entered the stage of increasing odds for a new pandemic, which prompts to seek out for new flu vaccines, because existing vaccines demonstrate only suboptimal effectiveness. With the Covid-19 pandemic, the possibility of using mRNA vaccines has been opened up, and a prospect of finding hemagglutinin (HA) gene mRNA-based new influenza vaccines seems very attractive. As a rule, the mRNA vaccine is a product of recoding, which ensures the mRNA stability. However, the results of mRNA recoding can be ambiguous. The purpose of this report is to analyze the features of genes and proteins and to consider opportunities and limitations in their recoding. Primary structures of NA proteins and relevant genes were retrieved from Internet publicly available databases. The amino acid composition and frequency of dipeptides, nucleotide and dinucleotide compositions, %GC, translational code and compositions of neighboring di- and tricodones, distribution along primary structure for explicit and synonymous mutations were determined. H1N1 and H3N2 subtypes have both specific and general features (limitations) in their genes, differing not only in the number of protein substitutions, but also in the number and distribution of gene synonymous codons, which do not manifest in the protein primary structure, but appear, apparently, as a hidden factor, which causes the low effectiveness of classical influenza vaccines. The identification of several limitations in gene structure suggests that its any modification (in any gene) must not contradict each of the restrictions established by nature. The frequency of CpG dinucleotides in all studied strains is low, but a potential for optimizing it in H1N1 strains due to the prohibition of the quartet in the gene for arginine-encoding codons is especially limited and can be implemented through synonymous codons of other amino acids (alanine, proline, threonine or serine). Compared to the H1N1 subtype, the H3N2 subtype can be expected to have more possibilities in constructing stable NA gene mRNA.

Novel &lt;i&gt;FLNC&lt;/i&gt; Gene Variant Associated with Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy, affecting approximately 1 in 500 people. It is the most common genetic cardiomyopathy inherited as a Mendelian trait in approximately 50% of patients, mainly due to pathogenic variants in genes encoding sarcomeric proteins. Mutations in the sarcomeric protein filamin C (&lt;em&gt;FLNC&lt;/em&gt;) gene, with a cytogenetic localization on 7q32.1, have been linked to hypertrophic cardiomyopathy, as they have been determined to increase the risk of ventricular arrhythmia and sudden death. We present the case of a patient with HCM recognized by magnetic resonance imaging and echocardiography with a family history of cardiopathies. The molecular study in this patient was performed by next-generation sequencing on the Illumina MiniSeq instrument, comparing the results with international databases. In genetic studies, a novel mutation in the protein &lt;em&gt;FLNC&lt;/em&gt; was detected. It is heterozygous, missence type. It is a variant where Cytosine is changed by timina at position 6305 of the &lt;em&gt;FLNC&lt;/em&gt; gene. This produces the change of the amino acid proline by leucine at position 2102 of the Filamin C protein. The rare variant is located in Ig-like domain 19 within the ROD2 domain. This variant report suggests that there may indeed be a direct relationship between &lt;em&gt;FLNC&lt;/em&gt; variants, mainly the ROD2 domain, and HCM. We think this new result should be considered for future genetic counseling of families affected by this type of cardiomyopathy.

Branched-chain amino acids modulate the proteomic profile of Trypanosoma cruzi metacyclogenesis induced by proline.

Trypanosoma cruzi, the causative agent of Chagas disease, has a complex life cycle that involves triatomine insects as vectors and mammals as hosts. The differentiation of epimastigote forms into metacyclic trypomastigotes within the insect vector is crucial for the parasite's life cycle progression. Factors influencing this process, including temperature, pH, and nutritional stress, along with specific metabolite availability, play a pivotal role. Amino acids like proline, histidine, and glutamine support cell differentiation, while branched-chain amino acids (BCAAs) inhibit it. Interestingly, combining the pro-metacyclogenic amino acid proline with one of the anti-metacyclogenic BCAAs results in viable metacyclics with significantly reduced infectivity. To explore the characteristics of metacyclic parasites differentiated in the presence of BCAAs, proteomics analyses were conducted. Metacyclics obtained in triatomine artificial urine (TAU) supplemented with proline alone and in combination with leucine, isoleucine, or valine were compared. The analyses revealed differential regulation of 40 proteins in TAU-Pro-Leu, 131 in TAU-Pro-Ile, and 179 in TAU-Pro-Val, as compared to metacyclics from TAU-Pro. Among these, 22%, 11%, and 13% of the proteins were associated with metabolic processes, respectively. Notably, enzymes related to glycolysis and the tricarboxylic acid (TCA) cycle were reduced in metacyclics with Pro-BCAAs, while enzymes involved in amino acid and purine metabolic pathways were increased. Furthermore, metacyclics with Pro-Ile and Pro-Val exhibited elevated enzymes linked to lipid and redox metabolism. The results revealed five proteins that were increased and four that were decreased in common in the presence of Pro+BCAAs, indicating their possible participation in key processes related to metacyclogenesis. These findings suggest that the presence of BCAAs can reshape the metabolism of metacyclics, contributing to the observed reduction in infectivity in these parasites.

Biotechnological methods for separation of pigs pancreas glands protein substances with membrane technologies

The pancreas gland (PG) is a secondary product of livestock processing; it contains a wide range of biologically active compounds. The purpose of this article is to analyze the efficiency of technological approaches for pancreas gland extraction with the help of trehalose and a glycine-proline mixture aimed for recovery and separation of the gland’s protein-peptide compounds. The extraction was conducted with 0.9% NaCl, 0.9% NaCl, with addition of 0.5 M trehalose (0.9% NaCl-0.5 M trehalose) and 0.9% NaCl with addition of 1% glycine and 0.1 M L-proline (0.9% NaCl-1% Gly-0.1M Pro), the ratio of pancreas gland to extractant was equal to 1:5. The concentration of the protein in the supernatants after their extraction was measured by the biuret reaction in a semi-automatic biochemical analyzer Biochem SA. The proteomic composition of the extracts and the native pancreas gland was assessed by one-dimensional Laemmli electrophoresis in a 12.5% polyacrylamide gel and by two-dimensional O’Farrell electrophoresis. When determining the intensity of the protein fractions, it was noted that the methodology of separation of protein-peptide mixtures extracted from the pigs pancreas gland with the extractant 0.9% NaCl-1% Gly-0.1M Pro, ensured the higher extraction of the proteins in comparison with the method of 0.9% NaCl-0.5 M trehalose. Notwithstanding the fact that application of amino acids (glycine and proline) mixture provided for a greater yield of proteins from the extract into the diafiltrate, the experiments in vitro showed that the diafiltrate obtained though trehalose featured higher activity. This may be explained by the fact that after dialysis removal of trehalose from the protein fraction with a molecular weight of less than 50 kDa, its residual quantities were still sufficient to prevent proteins aggregation and, as a consequence, the biological activity of the extracted proteins was preserved, while in the diafiltrate obtained through amino acids mixture where numerous protein aggregates were detected by 2-DE. This study allowed testing the biotechnological methodics on pig pancreatic tissues aimed to intensifying the extraction and separation of protein compounds. The results of the study are important for development of methodological approaches to obtaining the targeted substances for their further utilizing for various purposes.

Substrate preference of Tetrasphaera in dual PAOs synergistic EBPR system and its phosphorus removal performance

In this study, an alternated anaerobic/aerobic sequencing batch reactor (SBR) was employed to investigate the effect of the substrate conversion from casein hydrolysate (Cas aa) to a mixture of amino acids (glutamate, aspartate, glycine and proline) on the efficacy of nitrogen and phosphorus removal in an enhanced biological phosphorus removal (EBPR) system characterized by dual polyphosphate-accumulating organisms (PAOs), mainly focusing on the substrate preference of fermentative PAOs. The results indicated that a stable removal efficiency was found to be above 90 % as the substrate was converted to the mixture of amino acids. Meanwhile, the removal efficiency of ammonium eventually increased to over 95 % in stage III, despite an increase of ammonia nitrogen by hydrolysis with the rising proportion of mixed amino acids in influent. Moreover, shortening the anaerobic duration did not significantly affect the phosphorus removal performance, even enhancing anaerobic phosphorus release capacity. Nevertheless, the ammonia nitrogen removal was influenced. 16 s rRNA high-throughput sequencing results demonstrated that the detected fermentative PAO like Tetrasphaera in the EBPR system exhibited a clear preference for utilizing mixed amino acids and could cooperate with traditional PAO like Accumulibacter for phosphorus removal. In addition, the fermentation of amino acids mixture by Tetrasphaera was more pronounced and its abundance increased under the condition of a shorter anaerobic duration, leading to a relatively stable and high abundance of Accumulibacter in the presence of sufficient substrates from Tetrasphaera. However, considering the nitrogen removal performance and steady operation of the EBPR system, a longer anaerobic duration was more reasonable.

Integrated Molecular Docking and Experimental Analysis of Ni(II) Proline Dithiocarbamate Cytotoxicity in MCF-7 Breast Cancer Cells.

Chemotherapy is one of the most effective and widely used treatment types for breast cancer. The Ni(II) proline dithiocarbamate (Ni(II)ProDtc) complex has been synthesized as a potential anticancer agent with minimal systemic toxicity. The dithiocarbamate ligand, combined with the amino acid proline, holds promise as a radio chemotherapeutic target agent in tumors. The anticancer activity of a Ni(II) complex compound with a proline dithiocarbamate ligand was tested on the MCF-7 breast cancer cell line as part of a study on essential metal-based therapeutics. Molecular docking studies identified the active sites for the estradiol-estrogen receptor-α protein. The Ni(II)ProDtc complex was synthesized and characterized using melting point analysis, conductivity measurements, UV-Vis spectroscopy, and FT-IR spectroscopy. The cytotoxicity of the complex was evaluated in vitro using the MCF-7 breast cancer cell line. The UV-Vis spectrum at 246 nm indicated the π→π* intraligand transition of the CS2 group, while FT-IR analysis revealed peaks at 364-457 cm-1 corresponding to the bonding between Ni and Sulfur (S) and Oxygen (O) from proline. Further, the UV-Vis spectrum displayed bands at 212 and 676 nm, and FT-IR data at 387-691 cm-1, confirming the coordination of the Ni(II) atoms with sulfur, nitrogen, and oxygen in the isoleucine dithiocarbamate ligand. In vitro, cytotoxicity tests revealed that Ni(II)ProDtc induced cell death in the breast cancer cell line, showing significant morphological changes in MCF-7 cancer cells, with an IC50 value of 315.70 µg/mL. The Ni(II)ProDtc complex was successfully synthesized and demonstrates anticancer activity in MCF-7 breast cancer cells, indicating significant potential as an anticancer agent for breast cancer.

LC-MS-based serum metabolomics analysis and potential biomarkers for oxaliplatin induced neurotoxicity in colorectal cancer

Oxapliplatin-induced peripheral neuropathy (OIPN) is a significant adverse effect encountered in patients with colorectal cancer undergoing oxaliplatin therapy. However, the pathogenesis of OIPN remains unclear. This study aimed to identify potential diagnostic biomarkers for OIPN and discover the metabolic pathways associated with the disease. Serum samples were collected from 218 subjects, including patients with OIPN and control (CONT). The metabolite profiles were analyzed using nontargeted liquid chromatography-mass spectrometry (LC-MS) serum metabolomics method. Subsequently, differentially altered metabolites were identified and evaluated through multivariate statistical analyses. In this study, patients with OIPN and CONT were distinguished by ten significant metabolites. The levels of racemethionine, O-acetylcarnitine, stearolic acid, aminoadipic acid, iminoarginine, galactaric acid, and all-trans-retinoic acid were increased, whereas the levels of 3-methyl-L-tyrosine, 5-aminopentanoic acid, and erythritol compared were found to be diminished in patients with OIPN when compared to the CONT. Through receiver operating characteristic (ROC) curve analysis, racemethionine, stearolic acid, 5-aminopentanoic acid, erythritol, aminoadipic acid, and all-trans-retinoic acid were pinpointed as promising biomarkers for OIPN. Significantly altered pathways included amino acids (arginine biosynthesis, beta-alanine metabolism, arginine and proline metabolism, alanine, aspartate and glutamate metabolism, lysine degradation, and phenylalanine, tyrosine and tryptophan biosynthesis), lipid (linoleic acid metabolism and the biosynthesis of unsaturated fatty acids), and energy metabolism. This study, by identifying serum biomarkers and dissecting metabolic pathways, offers a groundbreaking perspective on the susceptibility mechanisms underlying OIPN. It stands as an invaluable resource for the adjunctive diagnosis of OIPN, with the potential to diminish the incidence of adverse reactions and to enhance the objectivity and reliability of clinical diagnoses of OIPN.